WAREHOUSE ONE AIR SUPPLY
By Larry Bush

- Ref: air equipment, air capacity, air compressor, compressor
efficiency, compressor capacity , industrial equipment and
engineering, industrial equipment and control
Summary:
"Plant air compressor efficiency is
commonly effected by other factors than the air compressor it's self.
Larry offers some insight in this article about his air equipment and
lines."
I have a rough sketch of the air system in the warehouse 1 area. This
sketch clearly shows the reason why we keep having air problems. The air
line supplying 90% of the air using equipment is only one inch pipe. There
are approximately 29 pieces of air using equipment that are tapped off the
one inch pipe coming out of the main warehouse 1 air supply line.
No matter that the air pressure on the main line is 100# psi. While
running, by the time the air is coming out of the yellow, air surge tank,
it is down to 78# psi. Then, by the time it gets to the Videojets, the
pressure is down to 62# psi. A slight drop trips the air switch at 60#psi.
The cost of installing a larger surge tank feeder pipe (2 inch) and
larger supply headers (2 inch) from the surge tank to the equipment risers
could be easily justified by the reduction in production stoppages,
equipment repair costs, and not being required to brightstack so much
product.
The low air pressure and volume could be causing problems on the other
air using equipment. The other stackers, casers and sleevers may be
partially air starved and the problems show up as when a pusher doesn't
push fast enough or doesn't push all the way.
There are formulas and tables in Mechanical Engineering Handbooks that
detail the exact size of piping needed to supply a given volume of air at
a required pressure for air using equipment. We are using a tremendous
amount of air in Warehouse 1 and the piping is grossly undersized. Even
with the booster air compressor, the volume and pressure are restricted by
the small size of the piping.
A temporary fix for the videojets would be, ½" air hoses tapped
from the riser at a point closer to the header and then to the videojets
(lines 1,2,3,4). This job could be carried out during a down day for 4 oz.
and the final upgrades could be carried out during the off season.
The air supply dryers and water separators at the air compressors are
not removing all the water from the air at the points of use. The air
system needs to be surveyed and evaluated in regards to the placement of
area and local air dryers and water and sediment separators in the air
system.
An increasing number of air using equipment breakdowns with a resultant
production downtime is occurring due to water and sediment in the air
supply. Videojets, sleevers, casers, Eagles, robots, and more use air and
electricity to operate. Dirty and wet air is as bad for the equipment as
low voltage and "noisy" electrical systems.
Water and oil separators and filters are a low cost solution to these
ongoing maintenance, repair and replacement problems. The equipment-size
filters and separators are totally overwhelmed by the lack of area-size
separators in the air systems. There are also automatic, low-point, water
removal devices available for placement at strategic points in each area.
Automatic air cutoffs tied into equipment on/off controls can also be
purchased and installed on air using equipment as needed. These automatic
cutoffs have a very short payback time and from then on you are making
money.
Every piece of air using equipment in all the plants can be checked and
each piece of equipment will show the effects of moisture and sediment
damage. We do not track the damage caused nor the production downtime
caused by the air supply problems, but if we did, I am certain it would be
far more than the one-time cost of the solution.
Larry Bush
Also watch for more articles by Larry Bush at ...
http://www.Reliability-Consultant.com/Industrial_Articles.htm
About the Author: Larry Bush
has been an electrician for 47 years, and in maintenance management for 22
years. Download his new e-Book "Maintenance
Policy and Procedures Manual" !!
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